Oh yes, his Medicinal Plants of the Northwest is always among my kitchen references. What I like about his style is the inclusion of the science behind it all. Im currently learning under one of his former students, Elaine Sheff. She recently opened Green Path Herb School and I've been helping her with references for her ebooks. She has lots of hands on
experience using and growing the herbs. Good folks for sure.
here is her website:
http://greenpathherbschool.com